Ymribiat; at first Hashem made adam with his feminine counterpart in one body; that was the ideal. Then she became corrupt, and separated. Hashem then made chava from adam.
Sheasani kirtzono can be explained two ways; one is that they are closer to the perfect ideal of ratzon Hashem, and the other is that it’s a modest acceptance of their lot in life. The second pshat isn’t as popular.